Iridium vs Copper plugs. 2011 4.0 Tacoma

My 05 4.0 came from the factory with iridiums. Denso on one side and ngk on the other.

I've been running iridiums in every single efi vehicle that i have owned or worked on in the last 15 years.

Never had or even heard of in person, iridiums causing a misfire or any other issue.

 

No it didn’t.

If came with copper Densos on one side and copper NGKs on the other.

 

Those are copper plugs

 

I wonder if those who had issues with iridiums got knock offs or purchased the wrong heat range plugs. Knock off iridiums have been around for a long time and if they are buying them on the cheap, it's possible they got knock off iridiums. Also, iridiums are pre-gapped and manually gapping them will also cause problems.

 

Could be but there has to be a reason why Toyota recommends not using them in the 4.0. They come in the 4cy tacomas but not the 4.0.

 

I haven't seen Toyota recommend against it in the 4.0, just that they specify it in the 4cyl. It most likely has to do with a higher CR in the 4-cyl. I have nothing against anyone using copper in their motors, but iridiums work if the plug is the correct plug for the application. Vehicle engineers don't always spec based on the best part available, but what is more cost effective for production. Iridiums cost more than the copper plugs in the 4.0 that work in the application. It doesn't mean that iridiums can't be used, just that it's more cost effective for the company to sell the vehicle with a satisfactory part and let the consumer pay for the maintenance at 30k.

I'm not here to advocate for iridiums or copper. Just my .20.

 

Toyota specifically says to only run iridium in the 4cyl tacoma.

Copper plugs perform better than iridiums. Only downside is shorter life span.




Copper Spark Plugs vs. Iridium and Platinum: Understand for Top Performance - CarsDirect

 

I've put 240k+ miles on my truck and I think I've changed them 3 times, maybe just twice.

 

Gap was almost the same.

 

Yes. But they do not recommend against using anything in the 4L.

 

Assuming you forgot to quote me.

What about my time for what? Changing my plugs at the same intervals you stated? 30 minutes every 3-4 years?

What a joke.

 

Also, coppers do not perform better than iridiums, nor do they perform worse. They just allow people to go longer without needing to change plugs. However, in high CR applications, iridiums are the norm because they do outperform copper.

 

You can try and slice it 100 different ways but if it comes stock with coppers and Toyota recommends copper, you should probably stick with copper.

And yes, there have been people on here with misfire issues after switching to iridium.

 

Not true...

Copper is a better conductor of electricity and iridium have higher resistance when they fire. Older ignition systems sometimes can't compensate for the higher resistance of an iridium plug. Same reason many older cars have trouble with them.

Do some reading. Talk to any high HP engine builder. Don't always go by the advertisements you read on google lol.

This is right from Champion spark plugs

https://www.championautoparts.com/P...otive-Spark-Plugs/Copper-Plus-Spark-Plug.html

Copper spark plugs run cooler and provide more power in performance driving situations. They are often installed as original equipment in turbocharged engines and engines with higher compression ratios. Copper spark plugs are also often used in older (pre-1980s) vehicles with a distributor-based ignition system.

Copper vs Iridium Spark Plugs: What’s the Difference? - AutoZone

Copper Spark Plugs vs. Iridium and Platinum: Understand for Top Performance - CarsDirect

 

Personally, I think Toyota recommends copper to meet emissions standards. The 4.0 is an older motor designed around older tech.

Most people have zero issues with iridiums, but some definitely have. Last thing I want to do is be in the middle of no where and have my truck start misfiring because I want my plugs to last 100k instead of 60k.

 

Iridium plugs are copper core with an iridium tip. Copper plugs are copper core with steel tips. The hellcat with a FI motor uses iridium so you don't get spark blow out. Most high HP FI motors use iridium for this purpose. Daily drivers won't notice the difference between copper and iridium.

 

These are the plugs NGK states will perform in my 2010 4.0. I currently have the copper plugs. I did have a set of iridiums in it for about 50,000 miles and had no issues and I'm not sure what I'll use next. I'll admit, I succumbed to the fear. I think those that had misfires with iridiums had other issues going on, like a bad plug, coil, or connection issue.
Denso has a similar breakdown.


https://ngksparkplugs.com/en/part-finder

 

lol your 4.0 Tacoma is no where near a hellcat. Newer motor designed to use iridium. The ignition system is designed to work with an iridium plug. This is comparing apples to oranges.

Most newer cars ignition systems are designed around using an iridium plug. The 4.0 is not one of them.

 

Haha. That's kind of my point. The spark jump takes approx 20% less energy to make the gap in an iridium plug. It's not a big deal to me. Like I said before. It's been in my truck for 140k miles and still drives great. Go with what you feel makes you comfortable.

 

Holy shit, this is about on par with the oil debate...